560 research outputs found
Prevalence of Bilirubin Encephalopathy in Calabar, South-South, Nigeria (A 5-Year Review)
Background: Bilirubin encephalopathy is the clinical syndrome associated with bilirubin toxicity to the central nervous system resulting in chronic and permanent sequelae. It has been estimated that approximately 60% of term babies and 80% of preterm babies develop jaundice within the first week of life.
Objective: To determine the prevalence, morbidity and mortality of bilirubin encephalopathy at our centre.
Methodology: A retrospective descriptive review of the case files of all babies diagnosed with bilirubin encephalopathy over the past 5 years from January 2010 to December 2014 was undertaken. Information retrieved from the case notes included age, sex, presence of fever, duration of illness, place of delivery, causes and treatment. The outcome measures such as discharged home, discharged against medical advice, and death were also noted.
Results: Out of a total of 2,820 babies, 21 (0.74%) were admitted on account of bilirubin encephalopathy. Of these 21, seventeen (81%) were males and four (19%) females giving M; F ratio of 5:1. Eighteen babies (85.7%) had pyrexia, 8(38.1%) and 6(28.6%) were hypertonic and hypotonic respectively on admission. Only 33.3% of the deliveries took place in the health facilities. The established factors responsible for jaundice included infections (septicaemia) (15/71.4%), ABO incompatibility (4/19.1%), and G6PDeficiency (2/9.5%). The mean maximum serum bilirubin of the subjects was 321.3μmol/l (242.5 – 440.3). The case fatality was 4/21(19%).
Conclusion: Neonatal septicaemia is associated with bilirubin encephalopathy. Therefore identification and prompt treatment is of utmost importance to avoid morbidity and mortality
HIV Sero-Prevalence among Infants Attending Immunization Centers in Calabar Metropolis, Cross River State, Southern, Nigeria
Introduction: Pediatric Human Immunodeficiency Virus (HIV) infection accounts for over 2.3% of all pediatric infections. Many HIV-infected infants are not identified until they develop symptoms and present with illness at health facilities. However, the six weeks immunization visit provides an opportunity for HIV-infected mothers and their exposed infants to be identified before symptoms occur. This study was therefore conducted to determine the HIV status of infants attending immunization clinics in Calabar with a view to enrolling them into treatment.
Subjects and Method: This cross sectional descriptive study was conducted in two Local Government Areas of Calabar consisting 22 selected immunization centers. Using the multistage sampling method, 330 infants were screened. Ethical clearance was obtained from the supervising Ministry of Health. Rapid test was conducted, reactive specimens had Deoxyribonucleic Acid Polymerase Chain Reaction (DNA PCR) done using Dried Blood Spots (DBS).
Results: A total of 330 infants aged 6 to 14 weeks were recruited, 173 (52.4%) were males while 157(47.6%) were females giving male to female ratio of 1.1:1. Mean age of the infants was 9.20 ± 3.1 weeks. Twenty four (24) tested positive for HIV antibodies, after HIV DNA PCR test, 14(4.2%) infants were infected. Antenatal care registration (ANC) and maternal ANC HIV status were statistically significant P=0.03 and P= 0.02 respectively.
Conclusion: HIV exposed and infected infants are still been missed and only diagnosed later in life. Therefore, maternal HIV status determination and early diagnosis at immunization centers is recommended to bridge the Prevention of Mother To child Transmission (PMTCT) gap
The challenge of abandonment for the sustainable management of Palaearctic natural and semi-natural grasslands
Disturbance by biomass removal is a crucial mechanism maintaining the diversity of Palaearctic grasslands, which are unique biodiversity hotspots. The century-long traditional land use of mowing, grazing and burning, has been fundamentally changed in many parts of the Palaearctic. Due to socio-economic changes, large areas of former pastures and meadows have been abandoned, leading to a succession towards secondary scrublands or forest and the encroachment of competitor grass species, all leading to a decrease in biodiversity. Here we report the causes and consequences of the cessation of traditional grassland management regimes, provide strategies for reducing the impact of abandonment and consider these from the perspective of sustainability. We consider the possibilities for initiating sustainable management regimes in the contemporary socio-economic environment, and discuss the prospects and limitation of alternative management regimes in the conservation of grassland biodiversity. These themes are also the core topics of this Special Feature, edited by the EDGG. We hope that this Special Feature will encourage steps towards more sustainable strategies for the conservation of Palaearctic grasslands and the integration of the sustainability perspective into their conservation. © by Orsolya Valkó 2018.Peer reviewe
Coral Host Cells Acidify Symbiotic Algal Microenvironment to Promote Photosynthesis
Symbiotic dinoflagellate algae residing inside coral tissues supply the host with the majority of their energy requirements through the translocation of photosynthetically fixed carbon. The algae, in turn, rely on the host for the supply of inorganic carbon. Carbon must be concentrated as CO2 in order for photosynthesis to proceed, and here we show that the coral host plays an active role in this process. The host-derived symbiosome membrane surrounding the algae abundantly expresses vacuolar H+-ATPase (VHA), which acidifies the symbiosome space down to pH ∼4. Inhibition of VHA results in a significant decrease in average H+ activity in the symbiosome of up to 75% and a significant reduction in O2 production rate, a measure of photosynthetic activity. These results suggest that host VHA is part of a previously unidentified carbon concentrating mechanism for algal photosynthesis and provide mechanistic evidence that coral host cells can actively modulate the physiology of their symbionts
Estimated Financial Performance of Exotic and Indigenous Tree Species in Smallholder Plantations in Leyte Province
This paper examines the need for estimates of financial performance of individual tree species for promoting smallholder forestry on Leyte Island in the Philippines, and presents some initial estimates of net present value and internal rate of return for smallholder plantings of indigenous and traditionally grown (exotic) tree species. Levels of profitability are found to be marginal for commercial production, particularly for native species. Data deficiencies are noted, and improved estimates of tree growth rates and rotation lengths in particular are needed to improve predictions of financial performance of smallholder forestry
Testing Rotational Mixing Predictions with New Boron Abundances in Main Sequence B-type Stars
(Abridged) New boron abundances for seven main-sequence B-type stars are
determined from HST STIS spectroscopy around the BIII 2066A line. Boron
abundances provide a unique and critical test of stellar evolution models that
include rotational mixing since boron is destroyed in the surface layers of
stars through shallow mixing long before other elements are mixed from the
stellar interior through deep mixing. Boron abundances range from 12+log(B/H) =
1.0 to 2.2. The boron abundances are compared to the published values of their
stellar nitrogen abundances (all have 12+log(N/H) < 7.8, i.e., they do not show
significant CNO-mixing) and to their host cluster ages (4 to 16 Myr) to
investigate the predictions from models of massive star evolution with
rotational mixing effects (Heger & Langer 2000). Only three stars (out of 34)
deviate from the model predictions, including HD36591, HD205021, and HD30836.
These three stars suggest that rotational mixing could be more efficient than
currently modelled at the highest rotation rates.Comment: 10 figures, 7 tables; accepted for publication in the Astrophysical
Journa
The role of rewilding in mitigating hydrological extremes: State of the evidence
Landscape rewilding has the potential to help mitigate hydrological extremes by allowing natural processes to function. Our systematic review assessed the evidence base for rewilding-driven mitigation of high and low flows. The review uncovers a lack of research directly addressing rewilding, but highlights research in analogue contexts which can, with caution, indicate the nature of change. There is a lack of before-after studies that enable deeper examination of temporal trajectories and legacy effects, and a lack of research on the scrub and shrubland habitats common in rewilding projects. Over twice as much evidence is available for high flows compared to low flows, and fewer than one third of studies address high and low flows simultaneously, limiting our understanding of co-benefits and contrasting effects. Flow magnitude variables are better represented within the literature than flow timing variables, and there is greater emphasis on modeling for high flows, and on direct measurement for low flows. Most high flow studies report a mitigating effect, but with variability in the magnitude of effect, and some exceptions. The nature of change for low flows is more complex and suggests a higher potential for increased low flow risks associated with certain trajectories but is based on a very narrow evidence base. We recommend that future research aims to: capture effects on both high and low flow extremes for a given type of change; analyze both magnitude and timing characteristics of flow extremes; and examine temporal trajectories (before and after data) ideally using a full before-after-control-impact design. This article is categorized under: Human Water > Value of Water Science of Water > Hydrological Processes Science of Water > Water Extremes Water and Life > Conservation, Management, and Awareness
Boron Abundances in Main Sequence B-type Stars: A Test of Rotational Depletion during Main Sequence Evolution
Boron abundances have been derived for seven main sequence B-type stars from
HST STIS spectra around the B III 2066 A line. In two stars, boron appears to
be undepleted with respect to the presumed initial abundance. In one star,
boron is detectable but it is clearly depleted. In the other four stars, boron
is undetectable implying depletions of 1 to 2 dex. Three of these four stars
are nitrogen enriched, but the fourth shows no enrichment of nitrogen. Only
rotationally induced mixing predicts that boron depletions are unaccompanied by
nitrogen enrichments. The inferred rate of boron depletion from our
observations is in good agreement with these predictions. Other boron-depleted
nitrogen-normal stars are identified from the literature. Also, several
boron-depleted nitrogen-rich stars are identified, and while all fall on the
boron-nitrogen trend predicted by rotationally-induced mixing, a majority have
nitrogen enrichments that are not uniquely explained by rotation.
The spectra have also been used to determine iron-group (Cr, Mn, Fe, and Ni)
abundances. The seven B-type stars have near solar iron-group abundances, as
expected for young stars in the solar neighborhood. We have also analysed the
halo B-type star, PG0832+676. We find [Fe/H] = -0.88 +/- 0.10, and the absence
of the B III line gives the upper limit [B/H]<2.5. These and other published
abundances are used to infer the star's evolutionary status as a post-AGB star.Comment: 31 pages, 14 figures. accepted to Ap
Decline in Physical Fitness From Childhood to Adulthood Associated With Increased Obesity and Insulin Resistance in Adults
To examine how fitness in both childhood and adulthood is associated with adult obesity and insulin resistance. A prospective cohort study set in Australia in 2004-2006 followed up a cohort of 647 adults who had participated in the Australian Schools Health and Fitness Survey in 1985 and who had undergone anthropometry and cardiorespiratory fitness assessment during the survey. Outcome measures were insulin resistance and obesity, defined as a homeostasis model assessment index above the 75th sex-specific percentile and BMI ≥30 kg/m^sup 2^, respectively. Lower levels of child cardiorespiratory fitness were associated with increased odds of adult obesity (adjusted odds ratio [OR] per unit decrease 3.0 [95% CI 1.6- 5.6]) and insulin resistance (1.7 [1.1-2.6]). A decline in fitness level between childhood and adulthood was associated with increased obesity (4.5 [2.6-7.7]) and insulin resistance (2.1 [1.5- 2.9]) per unit decline. A decline in fitness from childhood to adulthood, and by inference a decline in physical activity, is associated with obesity and insulin resistance in adulthood. Programs aimed at maintaining high childhood physical activity levels into adulthood may have potential for reducing the burden of obesity and type 2 diabetes in adults.<br /
Chemical Abundances of the Leo II Dwarf Galaxy
We use previously-published moderate-resolution spectra in combination with
stellar atmosphere models to derive the first measured chemical abundance
ratios in the Leo II dSph galaxy. We find that for spectra with SNR > 24, we
are able to measure abundances from weak Ti, Fe and Mg lines located near the
calcium infrared triplet (CaT). We also quantify and discuss discrepancies
between the metallicities measured from Fe I lines and those estimated from the
CaT features. We find that while the most metal-poor ([Fe/H] <-2.0]) Leo II
stars have Ca and Ti abundance ratios similar to those of Galactic globular
clusters, the more metal-rich stars show a gradual decline of Ti, Mg and Ca
abundance ratio with increasing metallicity. Finding these trends in this
distant and apparently dynamically stable dSph galaxy supports the hypothesis
that the slow chemical enrichment histories of the dSph galaxies is universal,
independent of any interaction with the Milky Way. Combining our spectroscopic
abundances with published broadband photometry and updated isochrones, we are
able to approximate stellar ages for our bright RGB stars to a relative
precision of 2-3 Gyr. While the derived age-metallicity relationship of Leo II
hints at some amount of slow enrichment, the data are still statistically
consistent with no enrichment over the history of Leo II.Comment: Accepted to A
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